Investigation of the multi-effect of angiotensin II on the biological behaviour of rat vascular smooth muscle cells in vitro

Objective To study the multi-effect of angiotensin Ⅱ on the proliferation ,migration and apoptosis of vascular smooth muscle cell (VSMC) in rats. Methods Recombinant adenoviral vector,AdCMV-AT2R,containing rat AT2 receptor gene was constructed by homologous recombination,and was used to transfer AT2 receptor gene to rat VSMC in vitro. Expression of AT2R mRNA was detected by RT-PCR and the rate of expression in VSMC was determined by flow cytometer;Cell proliferation was examined by incorporation of bromodeoxyuridine (BrdU);Migration of VSMC was tested by the method of modified Boyden′s chember. Apoptosis was quantified by flow cytometer. Results Expression of AT2R mRNA in VSMC was increased significantly after gene transfer. The peak value of expression rate was about 89.51% at 48 hours. When the expression of AT2R was at peak value,the OD value of BrdU incorporation were reduced by 51.6% ( P 0.01),and the number of VSMC migration was decreased by 62.2% ( P 0.05). The ratio of VSMC apoptosis in treated group and in contron group were 7.6%±1.6% and 32.1%±5.5% respectively. Conclusion The results indicated that the expression of AT2R can inhibit the proliferation and migration of rat VSMC and induce its apoptosis.